Unichip

Hardwiring a Unichip

 

The Unichip can be hardwired & custom tuned to just about any electronically fuel injected vehicle . It is important to understand that a car's computer only receives information via signals from sensors on the engine : the Unichip is a computer specifically designed to alter these signals . In other words the Unichip gives a Tuner the ability to change signals , tricking the ECU into making different decisions regarding timing , fueling & boost. We have wiring schematics and base maps available for a wide variety of vehicles. To tune a vehicle with a Unichip, the following are the bare minimum requirements:

1. A Unichip (Q version for normally aspirated applications & a Q+ for turbo).

2. A Unichip tuning kit as advertised here , downloaded onto a suitable laptop.

3. A good quality air-to-fuel ratio gauge & a good quality scantool.

A chassis dyno is very helpful.

When you order a Unichip, we pre-load it with a base map for the specific vehicle you're working on which greatly simplifies the tuning task since all the base parameters such as the Crank signal, Throttle Position Sensor, and Mass Airflow sensor are already configured.  We also provide a wiring schematic for the particular vehicle clearly showing how to connect the Unichip & we support many models of most major brand names like Toyota/Scion/Lexus , Jeep , Honda , Mini , BMW , Mazda , Porsche , Ford , Kia , Nissan/Infinity , VW also some Ferrari , Corvette, Lamborghini etc. Contact us via e-mail to verify that we have a wiring schematic for a particular vehicle. Signed up Tuners can look up schematics in the Tuner Area.

 

Videos & manuals in our Tuner Area explain the Unichip software & schematics in detail but here follows a brief outline of Unichip Tuning.

Here's an example of a Unichip wiring schematic :

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 How it works 

So Vehicle Make is self explanatory : this schematic is obviously for the second generation Scion XB 2.4 liter but also serves the 1.8 Corolla . P'nP Version means that there is a Plug 'n Play harness available for this type of ECU , should the Tuner want to add Plug 'n Play features to the kit , like the Unichip Plug 'n Play kit advertised for this particular vehicle on this website . Timing Style refers to the program that we're going to tell the Unichip to run so that we can manipulate the timing signal on this particular vehicle. Since we send the Unichip out pre-mapped with a base map the Tuner does not have to worry about this , the Timing Style will already be set-up in the Unichip . UNI Ver  refers to which version of the Unichip we use on this vehicle , in this case a Unichip Q since it's a normally-aspirated car.

Onto the drawing :  it shows 2 large rectangular plugs next to each other . These are the ECU plugs on the car's ECU , as they are viewed from the side where the wires go in , while the plugs are connected to the ECU .

The 24-pin plug on the right side of the schematic is the Molex-connector which plugs into the Unichip . When orientating this plug take note that we are viewing it from the side on which the wires enter the plug , with the retention lug to the right . When we send out a pre-mapped Unichip for a hardwire application we pre-load the Molex connector with the correct wires in the correct positions & we also supply a section of braided sleeving for a professional finish.

24-pin Molex connector functions for this schematic:

White/red : +12-volt

Brown : Ground

White : Throttle Position Sensor

Blue : Crank Position signal to Unichip

Yellow/blue : Unichip-modified Crank Position signal to the ECU

Green : Crank Position signal to Unichip

Black : Signal from the MAF to the Unichip.

Yellow/black : Unichip-modified MAF signal to the ECU.

Yellow : map selection .

Red : Roadspeed signal to Unichip

Red/yellow : Unichip-modified roadspeed signal to the ECU . In this case we clamp the roadspeed signal to the ECU at a certain spot , meaning the roadspeed-limiter has been removed.

The 10-Pin Molex-connector on the left side of the schematic houses the CAN wiring which we use for FLUX applications , as well as the yellow wire , which is the one we connect any of our map selection switches to : 2-way switch to allow switching between 2-maps in the Unichip , 3-way switch for 3 maps or a 5-way rotary switch for switching between 5 available maps.

Once the Tuner has wired the Unichip to the car's wiring harness according to the wiring schematic , the laptop is connected to the 6-pin port on the Unichip .  The Unichip software is started & the pre-loaded map on the Unichip is UPLOADED onto the Unichip software on the laptop so that the Tuner can use the EDIT function to change values in the timing & fueling tables. The screen looks like this:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

As we can see the Timing button is highlighted , so the values represent the timing values . Since the values are all zero at this stage it means that the timing curve would be completely stock . The numbers 1-13 on the left of the page represent the load sites , the numbers 1-24 across the top of the page represent the rpm sites.

When we click on the Fuel button the screen looks like this :

 

 

 

 

 

 

 

 

 

 

 

 

 

 Any of the values can now be edited , just like you would edit values in a regular spreadsheet . Making the values positive in this map would mean that the Tuner is adding fuel in the relevant load site : the higher the number , the more fuel is added.  After changes have been made the Tuner presses the DOWNLOAD button to send the updated map into the Unichip . Also note the Main Set , Map Set 2 etc. buttons on the left side of the screen . The Unichip is capable of storing 5 different mapsets for a vehicle . So the Tuner can tune the first Timing & Fueling screens in the Main Set , then tune Timing & Fueling screens in the other Map Sets completely differently . This is especially helpful in turbo applications where the first maps may be very mundane to accomodate low octane fuel & the other maps getting progressively more aggressive for higher octane/racing fuel.

Signed-up Tuners also have access to our How-to videos in the Tuner area which provide clear instructions on how to use the software & tuning in general.

 

What if I want to add an aftermarket turbo?

The problem with boosting a normally aspirated car is with the way that stock MAF & MAP sensors work. These sensors typically send 0-5 Volt signals to the stock ECU : low voltage when the pressure in the intake manifold is lower than ambient (ie. throttle closed or partially closed) , high voltage (5 Volt) when the pressure in the intake manifold is the same as ambient (ie. when the throttle is fully open). So when we start sending boost, ie. higher pressure than ambient down the intake this voltage from the MAF/MAP goes over 5 Volt. The stock ECU triggers a Check Engine Light because it thinks the MAF/MAP is faulty.

How do we fix this? Firstly we use the clamp feature in the Unichip software to clamp the 0-5 volt signal from the factory MAF or MAP sensor at 5 Volts so no matter what the boost goes to the stock ECU never sees more than 5 Volts so it never triggers a CEL. Then we add a Turbo Module to the Unichip set-up. This Turbo Module contains a special MAP sensor which also sends 0-5 Volt signals, with the difference that it sends the maximum 5-volts under boost conditions. We connect this signal to the Unichip & tell the Unichip to base it's look-up in the fuel map, as mentioned above, on this signal. So now we have a nice fuel map based on boost & we map our car's fueling to suit the boost.

What if I want to manage the boost?

By adding a Boost Solenoid to our Unichip/Turbo Module we can map the boost. We send a signal from the Unichip to the Turbo Module. The Turbo Module has a built in 12 Volt driver which drives the Boost Solenoid. The Boost Solenoid is teed into our turbo actuator hose. By using a special map, again rpm & load based like in the Fuel & Timing maps, in the Unichip program we can increase or decrease the duty-cycle on the Boost Solenoid to bleed off more or less boost on the turbo.

 

How about managing boost on a factory-turbo car?

Most modern factory turbocharged cars already have MAP/MAF sensors that read boost & they also have Boost Solenoids. This is very handy since we can manipulate these devices nicely to increase the boost.

The majority of factory turbo cars use the stock MAP sensor exclusively to sense maximum boost, & the MAF for calculating fueling values. So if we are going to increase the boost we have to clamp the stock MAP sensor to steer clear of CEL's & allowing the stock ECU to dump boost via the stock boost solenoid. Firstly we determine the voltage that the stock MAP sensor sends out when the car is boosting at its highest in stock form. We then clamp the MAP sensor at this voltage in the Unichip software. Therefore the ECU never sees more than the clamped value from the stock MAP sensor, it believes the boost to be stock & we don't get a CEL.

Next step is to manipulate the signal that the ECU sends to the stock boost solenoid. We use one of the frequency inputs/outputs like Option 3 or if we're already using that for something else like clamping roadspeed we use option 5 (Unichip Q+). We connect the signal from the ECU to pin 3 on the lower plug of the Unichip Q+ & connect the factory boost solenoid to pin 16. We go to the Option 5 spreadsheet by clicking on the Option 5 button on the bottom of the screen & we can now increase or decrease values to raise or lower the boost. Simple!